spy pen
Skip itPrices mostly outside the sweet spot ($2.37–$13.99) — this niche doesn't clear our bar today.
Returns
Incredible0.5%return rate — above 5% kills the launch gate
Conversion
Great8.3%search→purchase rate — share of searches ending in a sale
Brand share
Good70%top-5 brand share — brands hold most of the demand
Quality gap
Good4.4★avg incumbent rating — lower means beatable quality
Review moat
Good1,384.04avg incumbent reviews — the moat a new listing must climb
Competition
Okay58%top-5 click share — leaders hold, buyers still browse
Avg price
Bad£7.03avg listing price — sweet spot $15–$100
Growth
Bad-18.3%90-day search growth — must beat 0% to launch
Market size
Bad£42K£42K/yr · 72K searches
Price range
Bad£2.37–£13.99cheapest to priciest tracked listing — scored on the share inside $15–$100
According to Flapen's Amazon United Kingdom niche tracking, spy pen is a £42K/yr Amazon United Kingdom market (72K searches/yr). The top 5 brands hold 70% of demand. Demand peaks in Nov–Dec. Verdict: Skip it — 44/100.
Data updated Jul 29, 2026 · scored weekly · How we score niches
spy pen market data
- Units sold / yr
- 6K–8K
- avg 250–500/product
- Revenue / yr
- £42K–£56K
- units × avg price
- Conversion rate
- 8.3%
- Avg BSR
- #266
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 80%
- Out of stock
- 0.0%
- Avg brand age
- 39 months
- Avg seller age
- 184 days
Competition & brand share
The top 5 products take 58% of clicks — established leaders, but buyers still shop beyond them.Brands
17 rising
Sellers
48
Top-5 brand share
70%
Top 20: 100%
Top-5 click share
58%
Top 20: 96%
Open market
24%
- OFFCUP31%
- Faburo15%
- Tinc11%
- Toyseum8%
- DazSpirit6%
- SureMark5%
Demand & seasonality
Weekly Amazon search volume, last 104 weeks — -18.3% search growth over the last 90 days.Peak months: Nov, Dec · busiest ÷ quietest = 2.8×
Top spy pen search terms
- invisible ink pen with uv light19K/yr
- invisible ink pen15K/yr
- invisible pen9K/yr
- invisible pen with uv light7K/yr
- invisible ink6K/yr
- spy pens for kids7K/yr
- invisible ink pens for kids3K/yr
- spy pens4K/yr
- invisible ink pens3K/yr
Top spy pen products on Amazon
Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
All 24 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Faburo 7PCS Invisible Ink Pens Magic Pens for Kids with UV Light Magic Markers for Secret Messages Birthday Party Bags Filler Childrens Gifts
Faburo£4.494.5★1,396 rev
OFFCUP Invisible Ink Pen 14pcs Spy Pen with UV Light Magic Marker Pens with UV Light for Kids Spy Pens Invisible Ink for Writing Secret Message Party Bag Fillers for Kids
OFFCUP£5.314.5★593 rev
Tinc Invisible Ink Spy Pen | UV Light | Kids Party Bag Filler | Magic Marker for Secret Messages Multi One size
Tinc£2.374.5★983 rev
OFFCUP Invisible Ink Pen 7pcs Spy Pen with UV Light Magic Marker Pens with UV Light for Kids Spy Pens Invisible Ink for Writing Secret Message Party Bag Fillers for Kids
OFFCUP£4.314.5★593 rev
Toyseum 16 x Invisible Ink Pens With UV Light Spy Pens for Writing Secret Messages Fillers for Kids Party Bags Magic UV Marker for Boys & Girls Favours for Childrens School Prizes Pack of 16
Toyseum£6.684.4★109 rev
Newest
by launch date
Invisible Ink Pen for Boy Girl 14 Pcs Spy Pen for Kids with UV Light Disappearing Magic Pens for Kid Party Bag Fillers for Kids Teen Magic Invisible uv Marker Pens for Boys Girls Writing Secret
Nurhore£5.967 rev
Lepro UV Light Pen 365nm Ultraviolet Torch with Clip Blacklight Detector
Lepro£6.14321 rev
OFFCUP Invisible Ink Pen 14pcs Spy Pen with UV Light Magic Marker Pens with UV Light for Kids Spy Pens Invisible Ink Invisible Pen for Writing Secret Message Party Bag Fillers for Kids(A)
OFFCUP£4.87593 rev
pen 7pcs Spy with UV Light Magic Marker with UV Light for Kids Invisible Ink Party Bag Fillers
OFFCUP£4.23593 rev
Gammaeon Invisible Ink Pens Multifunction Security Marker LED UV Light Magic Marker Ballpoint Creative Secret Pen Office Supplies
Gammaeon£6.178 rev
Trending
90-day click momentum
THE TWIDDLERS 12 Pack Invisible Ink Pen and Notepad Set with UV Light - Secret Message Spy Toy for Childrens Party Bag Favours and Birthday Gifts
THE TWIDDLERS£10.894.4★
OFFCUP Invisible Ink Pen 14pcs Spy Pen with UV Light Magic Marker Pens with UV Light for Kids Spy Pens Invisible Ink for Writing Secret Message Party Bag Fillers for Kids
OFFCUP£5.314.5★
OFFCUP Invisible Ink Pen 14pcs Spy Pen with UV Light Magic Marker Pens with UV Light for Kids Spy Pens Invisible Ink Invisible Pen for Writing Secret Message Party Bag Fillers for Kids(A)
OFFCUP£4.874.5★
DazSpirit 30pcs Invisible Ink Pen UV Light Spy Pens for Kids
DazSpirit£12.714.5★
Toyseum 16 x Invisible Ink Pens With UV Light Spy Pens for Writing Secret Messages Fillers for Kids Party Bags Magic UV Marker for Boys & Girls Favours for Childrens School Prizes Pack of 16
Toyseum£6.684.4★
What buyers say about spy pen
What buyers praise and complain about, mined from review topics.What buyers love
“good quality”
“Good product worth the money”
“Does the job”
“Easy to use”
“Works really well”
“What fun for a 7yr old”
“Brilliant one for keeping privacy PRIVATE well done just try to post in discreet packaging as others can see”
“Good value for money durable”
“Comes with handy torch as well”
“Great selection if colour”
What buyers complain about
“Didnt work”
“battery connection not great”
“all same colour”
“Terrible quality”
“Parts missing”
Top return reasons
Common questions
- Is spy pen profitable to sell on Amazon United Kingdom?
- The niche generates £42K/yr across 25 tracked products. 90-day search growth is -18.3%. Flapen's verdict: Skip it (44/100).
- How competitive is the spy pen niche?
- 17 brands and 48 sellers compete. The top 5 products take 58% of clicks and top 5 brands hold 70% of demand.
- What do buyers complain about in spy pen?
- Top complaints mined from reviews: Functionality-Overall, Battery Life, Color. The return rate is 0.5%.
- When does demand for spy pen peak?
- Demand peaks in Nov–Dec; the busiest month runs 2.8× the quietest.
- What does it cost to enter the spy pen niche?
- Listings span £2.37–£13.99; the average listing price is £7.03 (sweet spot $15–$100). The average incumbent carries 1,384 reviews — the moat a new listing must climb.